Method and apparatus for heating wire



Nm, 17 1925. V1,561,579

o. c. TRAUTMAN METHOD AND APPARATUS FOR HEATING WIRE Filed April 2. 1924. 2 sheetssner 1 'llllllllll/ll/l/ flplzrlrlffllzf,

Nov. 17,1925. 1,561,579

` O.C. TRAUTMAN METHOD AND APPARATUS FOR HEATING WIRE Filed April 2. 11924 2 Sheetssneer 2 Atorzzzeyf (what lAny suitable or convenient type of electrical heating elements may Vbe employed. The type which I prefer and which I have .illustrated diagrammatically herein com- -prlses 'a sinuous' resistor 25 detachably mounted upon a refractory supporting plate 26, a plurality of these plates being employed and received in slots formed in refractory supporting blocks 27. Current is led -to and from these elements by suitable connections 28-28 here shown as housed inside protective castings S29- 29. The leadpot is formed at the end from which the wire issues with an aperture' 30 which receives a tubular casing 31 adapted for the reception of a thermo couple v(not shown) by reference to which the supply of current to the heating elementsis controlled either manually or automatically as will be understood. The cover 3 is also formed between the projections 5 with a vent aperture 32 which preferably communicates lwith the outer air by way of a vent tube 33 which discharges at a point outside of the casing.

. In ractice the trough lis filled with lead or ot er low melting point metal or alloy,

which is melted by the heat radiated thereto` from the resistance elements. Owing to the fact that the chambers 8 and 10 are thoroughly insulated from the outer air and have n0 communication therewith, the operation of the furnace is substantially the same 'under all. conditions. Preferably the surface of the bath inside the slots '4.-4 is covered with charcoal, coke, carbon, or other carbonaceous material to prevent oxidation of the lead. This substance exhibits the further advantage that by combiningf'with oxygen it reduces within the entire slot 20 a reducing atmosphere which prevents oxidation of the heated wire as it passes therethrough.

In case it is desired to heat a wire or rod of comparatively large cross section it is frequently desirable to heat it in stages, rather than to pass it immediately from room temperature to the maximum temperature of the bath. For this purpose Ir use av Aniultiple stage heating furnace as shown in Fig. 5. Here I have shown two lead pots lV and/1" mounted in separate chambers 8V I do not limit myself'to' any speciiic uses of my improved furnace. It finds its most important use in connection with the hardvening and tempering of spring wire by which I mean either round wire as used for machine springs or flat wire as used for clock and motor springs; pacities my improved furnace exhibits its greatest usefulness because of the uniformity of the product obtained therefrom; but it vnay likewise be used in annealing, and many Vother purposes,

and many changes in detail can be made as will be well understood by those skilled in the art.

Having thus described my invention, what I claim is:

l. The method of heat treating wire which contains the step of drawin the same through a mass of molten meta electrically heated by radiation while protecting such mass from loss of heat by convection. 'I

2. The method of heat treating wire which contains the step of drawing such wire be used in series but two 1s generally suficient.

and in these cathrough a mass of molten metal and heating said mass by radiation from luminouselec tric resistance elements while protecting such mass and elements from loss of heat by convection. f

The art of heating a moving wireto a4 predetermined uniform temperature which" consists in bringing the same in conducting contact with a mass of metal while A heatii'ig such mass by radiation and preventing heat loss by convection.

In testimony whereof, I hereunto atlix my signature.

osonn o.,.'rnnnrimn. 

